Hi,
I am a long time linux user and i figure out i should give netbsd a
try. I downloaded NetBSD 4.0 installed it on my system. I readhttp://www.netbsd.org/docs/current/
but it's not so well structured for my taste I just can't figure out a
few things.

I want to test the latest kernel (current) so i get it through anoncvs
(equivalent as taking the linux source with git i'm not lost here
:P). Now do I have to get anything else on a fresh installed NetBSD4.0
to compile and use the current kernel just for testing?
There are a lot of informations on that site i just can't figure out
which one to follow.

I don't want my whole system current just want to get the current
kernel compile it and put it along with the one i have so i can chose
to run it.

Unlike Linux which is a kernel with a userland slapped on top, each of the *BSD's are more tightly integrated -- meaning that the kernel & userland may not have as much latitude in being out of sync. I haven't tried what you are attempting, but you are free to experiment. It might work, but I can't promise that you will be successful.

Might I suggest, if you are just looking to experiment with NetBSD itself, and not involve yourself in cutting-edge development, that you stick with the -release and -stable branches. The -current branch is more for developers and beta/alpha-testers. If you are looking to get a taste of NetBSD, you would be better served to avoid the -current branch.

I feel the best advice you can receive at this point is to indicate that there is a mailing list specific to discussions about -current called current-users@. You can find information on subscribing at the following:

I suspect a number of people are apprehensive on discussing this matter further publicly due to the fact that you intentionally want to maintain a very distinct difference between the kernel's version & userland. As mentioned before, this may be acceptable in the Linux world, but in the *BSD world the two are much more tightly integrated. Most people are very carefully about making sure that the two are synchronized.

To track the current kernel you will also need a current userland (it wont work correctly with 4.0 userland) so install a current snapshot install cd (you can find it on ftp or just build it yourself).
To track the development you will only need cvs and build.sh.

I used to play with --current some years ago, because of a feature that i wanted and even the machine itself worked nicely , sometimes compiling the the --current failed badly.
U should use --current "if u have to" or if u want to play or test the hard way, otherwise use some stable source.
Reg /T